Single-roll crusher



w. KQLIGGETT.

SINGLE ROLL CRUSHER. APPLICATION FVILED JULY 10, 1916.

1 ,339 933, Patented May 11, 1920.

2 SHEETSSHEET 2- A FOR/V15) UNITED STATES PATENT. orrron.

K- L TT, or COLUMBUS, OHIO, ASSIGNOR "r THE JEFFREY MANUFAC- .TURINGCOMPANY,\OF COLUMBUS, OHIO. j v

SINGLE-ROLL CRUSHER.

' Specification of Letters Patent. Patented May 11, 1920;

Application filed July 10, 1916. Serial No. 108,486. I

To all whom it may concern Be it known that I, WILLIAM K. LIGGETT, acitizen of the United States, residing at Columbus, in the county ofFranklin and -Stateof Ohio, have invented certain new and usefulImprovements in Single- Roll Crushers, of which the following is aspecification, reference being had therein to the stoking furnaces hascreated a large demand for coal crushed to a small and uniform size.When the coal crushing machines heretofore manufactured have beenadjusted to produce the" desired fineness of product, their "capacityhasusually been reduced beyond vthe limit of profitable operation andan-unduly large portion of the coal has been reduced to dust.

The common expedient by which these difiicultis are avoided is the useof two crushing machines, one adapted to crush largerlumps to acomparatively small size being placed over "a second machine which isadapted to reduce the product of the first machine to the size required.Such a double .machine is necessarily expensive and re- ,1 quires arelativelypowerful driving mechanism; In the patentto Whiting, No.

. 1,045,763, is disclosed a machine comprising aroll rotating adjacent astationary breaker plate wherein the surface of the roll is thickly setwith a large number of relatively small crushing "teeth and a muchsmaller number {of. -relatively long hook-shaped "t-he. machine to becrushed, and the small 1 crushing teeth to crush it to the desired size.-"A,.smooth"br.eaker plate is normally sup- 3 ported'in' such mannerthat there shall be teeth,the -hookshaped teeth serving to draw 9.

the larger fragments of the coal down into only a' running clearancebetween its lower partand the tops of the crusher teeth. Inordenith'atthe longer ho'ok-shapedteethmay ;pas's, 'groov s' areprovided' in thebreaker T-plate ,;and the proportions of the teeth and 1 0 grooves "aresuch that there shall be only the necessary running clearance and thegrooves shall" be no wider thanthe-greatest desired:

. dimension of the fragments of coal in the -product. By thisarrangement of parts the throat through which the coal passes affords ofmine coal, including both large and small 7 fragments, and, by a singleoperation, re-

duce it uniformly to the small size suitable for modern automaticstoking furnaces.

A further object is to produce a machine of simple design and greatstrength in which the parts subjected to the greatest wear may bereadily and conveniently renewed.

Other objects will appear in the following. specification, wherein isset forth the preferred embodiment of my invention, reference being hadto the accompanying drawings of Which Figure 1 is a general plan view ofa machine embodying my present invention.

Fig. 2 is a side elevation of the machine shown in Fig. 1. I i

Fig. 3 is a transverse sectional view taken along the line 3-3 of Fig.1.

gig. 4 is a perspective view of the feeder r0 1Fig. 5 is a perspectiveView of the breaker p ate.

Referring to the drawings. 1, 1 are the end frames upon which thecrushing mechanism is mounted. Journal bearings 2 and 3 are formed inthese end frames and in these bearings are mounted the crushing rollshaft 4 and the feed roll shaft 5. The bearings are supplied with thecustomary removable caps "in order that the machine may be easily takenapart.

Keyed to the shaft 5 I is a pulley wheel 6 adapted to be connected. by asuitable belt with any convenient source of power by which the machinemay be driven.

*At the end of the shaft5 opposite to the pulley 6 ismounted a spurpinion 7 which engages with a gear 8 attachednto the roll shaft a todrive it. Mounted upon the shaft .4, betweenthe bearings 2, is a drum orroll 9 surface of the plate s 10 are formed elongated sharp-edged ribs12 extending parallel to the axis of the roll and, preferably, from endto end thereof. Preferably the front sides of the ribs are approximatelyradial to the axis of the roll. As will later appear, the ribs cooperatewith other parts in the crushing of the coal and the radial andcircu1nferential dimensions of the ribs bear a definite relation to thedesired size of the product.

Attached to the frame members 1 are removable end plates 13 and a rearcover plate 14 which serve to inclose the upper portion of the roll.This construction provides removable plates which, when in place, sealthe chamber within which the roll operates,thereby preventing the escapeof dust, and, when removed, allow access to the bolts 11 so that thesegmental sections 10 may be removed or replaced without the entiredismantling of the machine. A hopper 15 is attached to the upper edge ofthese plates and through this hopper is introduced the coal to becrushec. I

A breaker plate 16 is pivotally supported on a transverse shaft 17 atthe upper front side of the machine,.being disposed so that it and theroll form opposite, downward converging walls of a passage through whichthe coal moves to the final crushing points at the lower side of theplate. Said plate is provided at its lower side with a renewable shoe 18the entire operative surface of which is formed with elongatedsharp-edged ribs 19. These ribs are disposed in planes at right anglesto the ribs 12 on the roll and extend closely adjacent to the lastnamed. ribs, the two sets of ribs cooperating in a peculiar manner. asthe roll turns, to crush the coal to a uniform size. As in the case ofthe ribs of the roll, the dimensions of the ribs 19 bear a definiterelation to the size of the product. The shoe 18 is beveled along itstop and bottom edges to engage the clamping surfaces 20 and-21 formed onthe breaker plate 16 and the clamping plate 22 respectively. Theclamping plate 22 is secured to the lower edge of the breaker plate 16by a plurality of clamping bolts 23 by which it may be drawn against therenewable shoe 18 to lock itsecurely in place.

A shaft 24; extends through the breaker plate 16 near its lower end, andupon the projecting ends of this shaft are mountedthe eye bolts 25 whichextend rearwardly through the lugs 26 of the frame members 1.

Springs 27 are placed upon the extremities of these eye bolts outsidethe lugs 26 and are retained in place by nuts 28 by the ad? justment ofwhich the tension of the spring 27 may be varied. This provides acushioning of the breaker plate so that when an unusually hard piece ofmaterial is passed between the roll and the breaker plate, the

breaker plate may yield to relieve the strain without damage to themachine, after which the springs will immediately return. the breakerplate to its operative position.

It has been found that' when a crushing roll such as described isprovided with ribs '7 of a size appropriate to the production of finelycrushed coal, the larger lumps Wlll roll upon the top of the crushingroll and not be drawn down into the machine to be crushed. To overcomethis difii'culty I have provided a feeder roll 29 mounted upon the shaft5 intermediate the journal bearings 3 In order that the roll 29 may besecurely held against rotation relative to the shaft 5 that portion ofthe shaft which is intermediate the bearings 23 is formed square, andthe roll is built up'of sections 30 each of which is provided with asquare aperture 31, through which the shaft 5 extends. Upon each ofthese sections 30 is formed a nar row, radially elongated hook-shapedtooth 32 adapted to engage the larger pieces of coal and force themdownward between the roll andv breaker plate. These sections are soplaced on the shaft 5 that each tooth 32 isangularly displaced from thenext adjacent tooth, thus forming a spiral line of teeth around theroll. Formed on the face of the breaker plate 16 is a transverse ridge33 the upper face of which conforms closely to the curvature of the roll29 to prevent the passage of coal between the roll and the breaker plate16. The ridge 33 extends well under the feeder roll 29 and the lowerface of the ridge forms an upright abutment wall for the coal at pointsbetween the crusher roll and a vertical plane through the axis of thefeeder roll. To permit rotation of the roll 29 slots 34 are formed inthe ridge 33, and preferably in the adjacent parts of the body ofthebreaker plate 16, these slots permitting the passage of the elongatedfeeder teeth 32. As these teeth move downward and pass into the slots,it will beseen that they cooperate with the aforesaid abutment wall onthe breaker plate to effectively crowd the coal downward in the taperingpassageway toward the final crushing points. the teeth 32 in cooperationwith the breaker plate, many of the larger pieces of coal are partiallycrushed and the downward movement of the mass accordingly facilitated;Of course, in this downward feeding of the coal mass there is effectivecooperation be tween the'feeder roll 29 and the crushing roll 9; for,while the relatively low ribs of the crusher roll are not capable aloneof the coal 29 as will readily be understood In this positive feedingaction of from an inspection of Fig. 8. The upward movement of the teeth32 of the feeder roll has no effect. of course, upon the coal bemovement within the slots of the breaker plate.

In practical operation machines of this character are commonly arrangedto receive tom cars or from large grab buckets or by other rapid methodsof handling. In such cases there' will often be a load of several 'tonsof coal directly upon the crushing and feeding rolls. As the two rollsrevolve toward each other and downward, the lower parts ofthe-superimposed coal mass are engaged and drawn down into the taperingpassageway between the crusher roll and the breaker plate, the largerpieces of coal being effectively forced downward and partially crushed,as above described, by the? elongated teeth of the feeder roll, whilethe forwardly inclined ribs on the crusher roll exert a downward feedingaction on the smaller particles of the coal.

In the downward movement of the coal through the machine, it comes tothe final crushing points between the ribs of the roll and the ribs onthe shoe 18 of the breaker plate. The action of the two sets of ribs onthe coal is peculiar; the ribs, disposed as they are at right angles toeach other, tend to divide the stream of coal along'lines at rightangles to each other, cutting the coal into fragments of a generalcubical form rather than indiscriminately mashing it. Hence, while thecrushing action of the ribs is highly effective, there is much lesstendency to reduce much of the coal to dust than there is in the case ofprior machines in which the roll is formed with isolated teeth workingon a relatively plain or smooth faced breaker plate. It will beunderstood that the ribs both on the roll and on the breaker plate arespaced apart a distance approximately equal to the maximumpermissible'dimensions of the fragments of the product, and since, whenthe machine is adjusted for fine crushing, there is no space for largerfragments to pass through, the fineness of the product is assured.Furthermore, the cotiperative action of the two sets of ribs is suchthat while there is a relatively slight tendency to reduce the coal todust, and while the action is remarkably uniform, the capacity is notunduly reduced by the close setting of the plate and roll as in priormachines.

In the preferred form of construction illustrated in the drawings thecrushing ribs on the roll are shown as extending continuously the fulllength of the roll, but in referring to the ribs both of the roll and ofthe breaker plate as elongated, I intend simply to distinguish them fromisolated teeth such as have been used on the crushing rolls of priormachines and by the term elongated mean to indicate that the workingedges of the ribs are elongated to a length greater than the distancebetween the ribs on'the opposing element of the crusher. v

It is to be understood that cooperating sets of crusher ribs, such asare herein set forth, may beutilized in forms of construction differingmore or less radically in some respects from the structure hereindisclosed, and in my two co-pending applications of even date herewithand bearing the Serial Nos. 108,485 and 108,487, I have shown two otherforms of construction in which such ribs are embodied.

WVhat I claim is i 1. In apparatus for crushing coal, the combination ofa frame, two companion crushing elements oppositely mounted in the frameto form a downwardly tapering passage through which the coal passes tothe final crushing points, a feeding device supplemental'to the rollcomprising a series of elongated teeth mounted at the upper end of saidpassage to rotate around a trans- Verselyextending axis to engage thecoal and force it downward between the crushing elements, and means toprevent the engagement with the coal of said elongated teeth during theoutward and upward parts of the movement of rotation.

' 2. In an apparatus for crushing coal, the combination of a frame, twocompanion crushing elements oppositely mounted in the frame to form adownwardly tapering passage through which the coal passes to the finalcrushing points, and a positively acting feeding mechanism supplementalto the crushing element arranged to operate in the tapering passage wayto engage the larger fragments of coal and force them downwardly throughthe tapering passage.

3. In apparatus for crushing coal, the combination of a frame, acrushing roll rotatably mounted in the frame, a breaker plate mounted inthe frame at one side of the roll to cooperate therewith, the said plateplate mounted in the frame at one side of the roll to cooperatetherewith, the said roll and plate forming opposite downwardlyconverging walls between which the coal points, and means or feeding thecoal-down- Wa'rdly between the converging walls comprising atransversely extending cylinder rotatably mounted between the crushingroll and the breaker plate and having radially elongated teeth, thebreaker plate being formed adjacent the feeding cylinder with slots intowhich the said elongated teeth pass during their upward movement.

5. In apparatus for crushing coal, the combination of a frame, acrushing roll rotabably mounted in the frame, a breaker plate mounted inthe frame 'at one side of the roll to cooperate therewith, the said rolland. plate forming opposite walls of a downwardly tapering passagethrough which the coal passes downwardly to the final crushing points,and means for feeding the coal downwardly between the converging wallscomprising a transversely extending cylinder rotatably mounted betweenthe crushing roll and the breaker plate and having radially elongatedteeth, the breaker plate being shaped to form'an upright abutment walldisposed beneath the feeding cylinder at points in vertical planesbetween the crusher roll and the axis of the feeder cylinder and thesaid abutment wall and adjacent partsof the breaker platebeing formedwith slots into which the feeder teeth intermittently. pass in theirrotational movement.

In testimony whereof I aflix my signature in presence of two witnesses.

lVILLIAM K. LIGGETT.

Witnesses HARRY C. DEAN, DUDLEY T. FISHER.

